It seems that there is a common misconception that a power meter is capable of telling you how many Calories you burn in a workout. Something I hear all the time from athletes is
"That was a really hard ride... I burned 3300 Calories"
to which I reply, "How do you know you burned 3300 Calories?"
and they answer, "Well, because that's what it says on my PowerTap (under 'e')"
In truth, this number refers to the amount of work you did on your ride (measured in kilojoules or kJ), not the Calories (kCal)you burned. I believe that the reason this misconception exists is because under steady state conditions, a very efficient rider will burn approximately the same number of kCal as kJ. But don't make the mistake of thinking that they are the same thing.
First, let's take a step back to 8th grade Physics class. Work is a measure of energy transfer, calculated as Force x distance. It requires a given amount of work to move an object from one place to another. You can think of moving a pile of bricks from one side of the room to another, walking up a set of stairs, or riding your bike up a hill. Work is not time dependant so whether you do the work fast or slow, the work required does not change.
Power is calculated as Force x Velocity (or Energy/time). So, extrapolating, Energy = Power x time. What this means is that if I move the bricks faster, run up the stairs and sprint up the hill the power is greater and the time is lower. If I move the bricks slowly... walk slowly up the stairs... ride slowly up the hill... the power is lower and the time is greater. Either way... same amount of work.
A Calorie is also a unit of energy, but when we talk about Calories in this context we are usually referring to the amount of energy the body is burning. The conversion from kJ to kCal is 4.184 to 1. So in reality, if you do a 3300 kJ ride, this is only equivalent to 789 kCal. However, this makes the assumption that every Calorie your body burns actually goes into work done on the bike, which is incorrect. In fact, only 1 out of every 4-6 Calories you burn goes into this work. So what happens to the other 75-85% of the Calories? Some are used to support vital body functions, but the majority are lost in heat. And of course, all that heat produced means that your body has to work even harder (and thereby burn more Calories) to cool itself off.
This is where metabolic efficiency comes into play. An efficient pro cyclist on a steady endurance ride is probably close to the 25% efficiency mark (meaning that 1 out of 4 of their Calories ends up helping to move the bike forward. So although 3300 kJ is only equal to 789 kCal, 25% efficiency would mean that that this rider burns 3156 kCal during this effort. A less efficient rider or a rider completing a more variable effort (e.g. race, group ride, etc.) will be closer to 18% efficiency (1 out of every 5.6 kCal goes into moving the bike forward) so this rider would burn 4383 kCal for the same 3300 kJ ride.
No before you go start to get depressed about being so inefficient, think about this: a 165 pound cyclist (me, to be specific) generally does about 35-40 kJ of work per mile. Let us assume that I have a metabolic efficiency of 23%. This means that I burn 36- 42 kCal per mile. A Toyota Prius hybrid gets about 38 miles per gallon. About 159,000 kJ are stored in a gallon of gasoline (37,975 kCal) so it requires 999 kCal to go 1 mile. This means that when I ride my bike I am 24-28 times as efficient as a Prius, or alternatively, for a car to be as efficient as a bicycle, it would have to get 784-912 miles per gallon. Think about that the next time your are thinking about ways to go green!
Thursday, May 22, 2008
Thursday, April 10, 2008
Is the Sport of Duathlon Dead? Not on the East Coast!
Do thoughts of a mass start swim with 300 plus eager triathlon-types haunt your dreams? Or is it the fear of having to swim in a body of water that might not be as peaceful as that calm pool and the ever helpful blue line along the bottom to guide your progress? Just what lurks in the dark depths of all those lakes and rivers we so freely jump into? Maybe nothing at all, but if you were a spectator for several of the recent New York City triathlons, watching the legions of triathletes emerge from the Hudson river with a slight brownish hue to their complexion might leave you wondering!
With countless triathlons under my belt, I still get nervous before the start of the swim and certainly think twice about those non-wet suit swims (the wet suit is my version of a safety blanket). Does this dissuade me from participating in triathlons? No. My fear washes away once I safely reach that first buoy with my goggles still firmly in place. As the numbers participating in triathlons grows exponentially, are these multi-sport addicts over-looking something which on paper appears far easier, yet in reality might be an even more challenging event – the Duathlon?
Just what is a duathlon (or as some refer to it – biathlon)?
No, we are not talking about that obscure winter sport we only see on television during a Winter Olympic year. You know, the one where the athletes cross-country ski and shoot at tiny targets with 22 caliber rifles carried on their back. While that might be the more global sporting definition of a biathlon, what we are talking about is a triathlon without the swim. Let’s be frank, just as Lance Armstrong revived American cycling, the Ironman has done wonders to the sport of triathlon. In fact, many multi-sport athletes might not even know of the existence of the sport of duathlon. I am willing to bet if you told your co-workers you competed in a duathlon over the weekend the likely response would be a look of utter confusion. However, mention you competed in a triathlon and all will not only understand, but perhaps share their own triathlon aspirations – as the triathlon has replaced the marathon as the ‘in’ endurance event for weekend warriors alike!
A few seasons ago, Inside Triathlon ran a story entitled ‘Demise of Duathlon’. The story cited the go-go years of duathlon, which in the late 80s and 90s had its own national series sponsored by none other than Coors Light (and (boasting huge prize lists for the professionals). Unfortunately, Coors Light left the sport long ago, being replaced on a smaller scale by Dannon, who left the sport in 2004 citing declining participation. While many professional duathletes have followed the money train to triathlons, which is now getting the lion share of the national advertising dollar thanks in part to the growing legions of Ironmen, does this mean duathlon is dead for us amateurs? Of course not!
Every spring for the past decade I have toed the start line for the annual March Madness biathlon in New York’s Central Park, an event which has seen sell-out crowds of over 600 duathletes for the past several years. While quite common in triathlons, a sold-out duathlon is a rare occurrence in most parts of the country. That is not the case for this early season New York City classic (fittingly called the March Madness Biathlon), as dormant multi-sport athletes emerge from their hibernation to test their early season form. This event has also seen some big names grace the winner’s podium over the years, including multi-sport legends Mark Allen (who won here in 1986) and Kenny Souza (won in 1987). Does Dan Honig, president and founder of the New York Triathlon Club (and the one responsible for the March Madness race), think the sport of duathlon is dead? Doubtful, as the New York Triathlon Club schedule of events has been steadily growing every year since the mid-80s and will commonly feature a dozen or more duathlons each season, with many running along side of triathlons – a recipe that is growing in popularity for race promoters.
Personally, I got my multi-sport start with duathlons. A cyclist in high school and college, I had always done some running on the side, so duathlons seemed an easy choice. For years I resisted the urge to do triathlons for several reasons. My first excuse was the most simple – time. Where was I going to find time to swim? Cycling and running already occupied the majority of my free time, so how could I conceivably fit in another sport (especially one I had not participated in since college?) My second excuse would be categorized by my therapist as a ‘fight or flight’ response (ie. the thought of a mass start swim scared the heck out of me). Ironically, it was a running injury that forced me into the pool and my triathlon career began. Have I forgotten about duathlons? No way, as I am a firm believer that the best way to prepare for a triathlon is a nice fast early season duathlon!
But I am a Triathlete – why should I do a duathlon?
When I competed in my first duathlon, my idea of a transition area was a place to put my Green Bay Packers folding chair as I leisurely swapped my running shoes for cycling shoes. With two nearly identical transitions, a duathlon is the perfect opportunity to practice your transition skills. Sure, there is no wetsuit to contend with, but now you have to change shoes twice and you will quickly learn that every second counts as the pack of racers tends to stay closer together when there isn’t a swim to break it up.
Besides the transition area practice, a duathlon is the ultimate combination workout (or ‘brick’ as we have come to call them). As multi-sport athletes, we have to teach our body to perform a variety of athletic tasks while fatigued. If you think the running segment of a triathlon is challenging after swimming and biking, try running twice in an event - it will make that sprint triathlon feel like a walk in the park! Trust me when I say a duathlon is the ultimate ‘brick’ workout.
The final appeal for the duathlon is the lack of a swim – something many of us could do without on occasion. I am not afraid of the water, but I can do without that guy who refuses to swim in a straight line and thus swims over the back of your legs, or better yet feels you in his draft and does a dolphin kick that catches your nose and rips the goggles from your face. That is when my version of panic sets in! Trust me when I say the swim portion of a triathlon does get easier with experience. Perhaps it is this not so uncommon fear of the water has kept potential multi-sport athletes from joining our ranks? If so, what better way to get you feet wet, than with a duathlon?
While the sport of duathlon might not have the same support and following across the country, the Mid-Atlantic States are full of duathlons, with a race calendar that stretches from March through October (check out my own list of local duathlons below). To find out more info on duathlons, go to http://www.usatriathlon.com/Duathlon/duathlon_home.htm or visit the only website dedicated to the sport (www.duathlon.com).
2008 Duathlon Calendar for the Mid-Atlantic region (not all races listed)
Mar 30 - Virginia Duathlon (5k/23mi/5k), VA
Mar 30 - March Madness Du (2mi/12mi/2mi), NY
April 6 - Brandywine Duathlon (5k/30k/5k), DE
April 13 - Powerman Alabama (8k/50k/8k), AL
April 13 - Brooklyn biathlon (2mi/10mi/2mi), NY
April 26 - Duathlon Nationals (10k/40k/5k), VA
April 27 - Bronx Biathlon (3mi/20mi/3mi), NY
May 4 - Trooper biathlon (2mi/14mi/2mi), NY
May 18 - Queens biathlon (3mi/18mi/3mi), NY
May 24 - Hammonton Du (& tri), NJ
June 1 - Belleplain du (1mi/15mi/3mi), NJ
June 8 (& Aug 17) - Harriman State Park duathlon (& tri), NY
June 14 - Thundergust duathlon (& tri), NJ
June 22 - Flat as a Pancake duathlon (& tri), Staten Island, NY
June 22 - Westchester biathlon, Rye, NY
July 6 - Philadelphia Women’s duathlon (& tri), Philly, PA
July 13 - Hudson Valley Du (& tri), NY
July 19 - Sunset Sprint duathlon (& tri), Bridgeton, NJ
July 20 - Putnam Du (& tri), Putnam NY
Aug. 17 - Lums Pond duathlon (& tri), Bear, DE
Sept. 7 (& Oct. 5) - Central Park duathlon, New York, NY
Sept. 13 - Fox Run Du, DE
Sept. 14 - Skylands duathlon (& tri), Clinton, NJ
Sept. 20 - Vineland Exchange Club Du (& tri), NJ
Sept. 21 - Endless Summer Du, Long Beach island
Sept. 28 - Cape Henlopen duathlon (& tri), Bear, DE
By Mikael Hanson
Director of Performance - NYC
With countless triathlons under my belt, I still get nervous before the start of the swim and certainly think twice about those non-wet suit swims (the wet suit is my version of a safety blanket). Does this dissuade me from participating in triathlons? No. My fear washes away once I safely reach that first buoy with my goggles still firmly in place. As the numbers participating in triathlons grows exponentially, are these multi-sport addicts over-looking something which on paper appears far easier, yet in reality might be an even more challenging event – the Duathlon?
Just what is a duathlon (or as some refer to it – biathlon)?
No, we are not talking about that obscure winter sport we only see on television during a Winter Olympic year. You know, the one where the athletes cross-country ski and shoot at tiny targets with 22 caliber rifles carried on their back. While that might be the more global sporting definition of a biathlon, what we are talking about is a triathlon without the swim. Let’s be frank, just as Lance Armstrong revived American cycling, the Ironman has done wonders to the sport of triathlon. In fact, many multi-sport athletes might not even know of the existence of the sport of duathlon. I am willing to bet if you told your co-workers you competed in a duathlon over the weekend the likely response would be a look of utter confusion. However, mention you competed in a triathlon and all will not only understand, but perhaps share their own triathlon aspirations – as the triathlon has replaced the marathon as the ‘in’ endurance event for weekend warriors alike!
A few seasons ago, Inside Triathlon ran a story entitled ‘Demise of Duathlon’. The story cited the go-go years of duathlon, which in the late 80s and 90s had its own national series sponsored by none other than Coors Light (and (boasting huge prize lists for the professionals). Unfortunately, Coors Light left the sport long ago, being replaced on a smaller scale by Dannon, who left the sport in 2004 citing declining participation. While many professional duathletes have followed the money train to triathlons, which is now getting the lion share of the national advertising dollar thanks in part to the growing legions of Ironmen, does this mean duathlon is dead for us amateurs? Of course not!
Every spring for the past decade I have toed the start line for the annual March Madness biathlon in New York’s Central Park, an event which has seen sell-out crowds of over 600 duathletes for the past several years. While quite common in triathlons, a sold-out duathlon is a rare occurrence in most parts of the country. That is not the case for this early season New York City classic (fittingly called the March Madness Biathlon), as dormant multi-sport athletes emerge from their hibernation to test their early season form. This event has also seen some big names grace the winner’s podium over the years, including multi-sport legends Mark Allen (who won here in 1986) and Kenny Souza (won in 1987). Does Dan Honig, president and founder of the New York Triathlon Club (and the one responsible for the March Madness race), think the sport of duathlon is dead? Doubtful, as the New York Triathlon Club schedule of events has been steadily growing every year since the mid-80s and will commonly feature a dozen or more duathlons each season, with many running along side of triathlons – a recipe that is growing in popularity for race promoters.
Personally, I got my multi-sport start with duathlons. A cyclist in high school and college, I had always done some running on the side, so duathlons seemed an easy choice. For years I resisted the urge to do triathlons for several reasons. My first excuse was the most simple – time. Where was I going to find time to swim? Cycling and running already occupied the majority of my free time, so how could I conceivably fit in another sport (especially one I had not participated in since college?) My second excuse would be categorized by my therapist as a ‘fight or flight’ response (ie. the thought of a mass start swim scared the heck out of me). Ironically, it was a running injury that forced me into the pool and my triathlon career began. Have I forgotten about duathlons? No way, as I am a firm believer that the best way to prepare for a triathlon is a nice fast early season duathlon!
But I am a Triathlete – why should I do a duathlon?
When I competed in my first duathlon, my idea of a transition area was a place to put my Green Bay Packers folding chair as I leisurely swapped my running shoes for cycling shoes. With two nearly identical transitions, a duathlon is the perfect opportunity to practice your transition skills. Sure, there is no wetsuit to contend with, but now you have to change shoes twice and you will quickly learn that every second counts as the pack of racers tends to stay closer together when there isn’t a swim to break it up.
Besides the transition area practice, a duathlon is the ultimate combination workout (or ‘brick’ as we have come to call them). As multi-sport athletes, we have to teach our body to perform a variety of athletic tasks while fatigued. If you think the running segment of a triathlon is challenging after swimming and biking, try running twice in an event - it will make that sprint triathlon feel like a walk in the park! Trust me when I say a duathlon is the ultimate ‘brick’ workout.
The final appeal for the duathlon is the lack of a swim – something many of us could do without on occasion. I am not afraid of the water, but I can do without that guy who refuses to swim in a straight line and thus swims over the back of your legs, or better yet feels you in his draft and does a dolphin kick that catches your nose and rips the goggles from your face. That is when my version of panic sets in! Trust me when I say the swim portion of a triathlon does get easier with experience. Perhaps it is this not so uncommon fear of the water has kept potential multi-sport athletes from joining our ranks? If so, what better way to get you feet wet, than with a duathlon?
While the sport of duathlon might not have the same support and following across the country, the Mid-Atlantic States are full of duathlons, with a race calendar that stretches from March through October (check out my own list of local duathlons below). To find out more info on duathlons, go to http://www.usatriathlon.com/Duathlon/duathlon_home.htm or visit the only website dedicated to the sport (www.duathlon.com).
2008 Duathlon Calendar for the Mid-Atlantic region (not all races listed)
Mar 30 - Virginia Duathlon (5k/23mi/5k), VA
Mar 30 - March Madness Du (2mi/12mi/2mi), NY
April 6 - Brandywine Duathlon (5k/30k/5k), DE
April 13 - Powerman Alabama (8k/50k/8k), AL
April 13 - Brooklyn biathlon (2mi/10mi/2mi), NY
April 26 - Duathlon Nationals (10k/40k/5k), VA
April 27 - Bronx Biathlon (3mi/20mi/3mi), NY
May 4 - Trooper biathlon (2mi/14mi/2mi), NY
May 18 - Queens biathlon (3mi/18mi/3mi), NY
May 24 - Hammonton Du (& tri), NJ
June 1 - Belleplain du (1mi/15mi/3mi), NJ
June 8 (& Aug 17) - Harriman State Park duathlon (& tri), NY
June 14 - Thundergust duathlon (& tri), NJ
June 22 - Flat as a Pancake duathlon (& tri), Staten Island, NY
June 22 - Westchester biathlon, Rye, NY
July 6 - Philadelphia Women’s duathlon (& tri), Philly, PA
July 13 - Hudson Valley Du (& tri), NY
July 19 - Sunset Sprint duathlon (& tri), Bridgeton, NJ
July 20 - Putnam Du (& tri), Putnam NY
Aug. 17 - Lums Pond duathlon (& tri), Bear, DE
Sept. 7 (& Oct. 5) - Central Park duathlon, New York, NY
Sept. 13 - Fox Run Du, DE
Sept. 14 - Skylands duathlon (& tri), Clinton, NJ
Sept. 20 - Vineland Exchange Club Du (& tri), NJ
Sept. 21 - Endless Summer Du, Long Beach island
Sept. 28 - Cape Henlopen duathlon (& tri), Bear, DE
By Mikael Hanson
Director of Performance - NYC
Friday, December 28, 2007
Zen and the Art of the Endurance Ride
Most of us remember Eddy Merckx's response when he was asked for his advice for young riders aspiring to become professionals: "Ride Lots". Though Merckx is thought by many to be the greatest rider of all time, this sort of simplistic training methodology bares little resemblance to the highly specific and periodized, science based training plans of the stars of today. And in truth, even the great Eddy had a lot more structure to his training than he let on.
The difference between "just riding" and actually training with a purpose is that when you train you must recognize that every workout has a purpose. This is easy for us to forget in the fall and winter months when many of us are coming off of less structured periods of training and beginning base training composed primarily of endurance rides. Yet many of us look forward to this time of the year as a time when we can enjoy the longer, lower intensity, more social rides without the stress of a lot of intensity training, racing and traveling. Don't be misled though; there is much more to an endurance ride than "just riding". Like any other workout, an endurance ride serves a specific purpose and if done incorrectly can at best be of little training value and at worst lead to over-reaching (and ultimately over-training), injury and burnout.
Purpose of endurance rides:
- Mechanical efficiency. Though one-legged drills, fast cadence drills, riding a fixed gear bike and rollers can all help make your pedal stroke more efficient, the simple act of pedaling thousands or even millions of pedal strokes may do the most to make your pedaling as smooth and even as possible. All of this repetition should also help you to identify any bike fit or body misalignment issues (i.e. if you need to see a doctor or a chiropractor)
- Metabolic efficiency. Lower intensity rides (zones 1-3) will help teach the body to burn fat as a primary energy source. When we do Lactate Threshold tests in our lab, we can always tell when people need to spend more time developing their aerobic base because they accumulate lactic acid even at relatively low intensities (zone 1-2). Since lactic acid is a bi product of anaerobic energy production, premature lactate accumulation is a sure sign that these riders need to develop the ability to efficiently metabolize fat for energy. Burning muscle glycogen (which is in limited supply) for energy rather than fat (which there is a large supply of even in the leanest athletes) means that you will not be able to make the key high intensity efforts when it really counts.
- Improve the body's ability to transport blood and oxygen. When we talk about "aerobic fitness" this is primarily what we are talking about. High intensity exercise can also accomplish this, but these levels cannot be sustained as long and repeated bouts of high intensity exercise every day can lead to overreaching, illness and injury. Development of aerobic fitness will mean that the body will respond better to the intensity workouts that come later on.
- Muscular strength. Though muscle mass will be generated more effectively in the gym, on the bike strength training is what will make this muscle mass more functional on the bike. In order to keep heart rate and power in zone 2 uphill, it is often necessary to pedal at very low rpms. If you are able to stay seated with good form this can be an opportunity not only to keep your heart rate and power down, but also to work on cycling-specific muscular strength.
- Fat Loss. Though you will more fat in a 1 hour ride at LT than you will on a 1 hour endurance ride, you won't be able to do 1 hour LT rides every day, whereas most experienced riders are capable of completing 4, 5, and even 6 hour endurance rides on a regular basis. A typical cyclist will burn 350-800 kCal.hour on the bike, so if you need to shed some extra pounds before spring there is no better way to do it than to add endurance volume while monitoring your Caloric intake. You will still have to consume more Calories when you increase your training volume though. Cut out desserts, junk food and alcohol and cut portion size at dinner, especially on your light days or off days. Don't starve yourself on the bike. The more you eat on your rides, the more Calories you will burn and the better you will feel. If you are losing more than 1 pound per week (a caloric deficit of 500 kCal), you are losing weight too fast and should increase energy consumption and/or reduce training volume.
So how do we accomplish all of these goals most appropriately? When I examine power files from an athlete's endurance ride, this is what I look for:
- No more than 5% of the time above zone 2 heart rate. There will be times where it is difficult if not impossible to keep your heart rate down in zone 2. A little time in zone 3 is OK, but try to avoid extended periods above the upper limit of zone 2 HR.
A graph of cadence distribution during one group ride shows 19% of the time coasting (0 rpm)
- Steady power output and heart rate throughout the ride without a significant fade. If a rider's power drops dramatically towards the end of the ride, it is probably a sign that they didn't eat enough. If their heart rate rises dramatically, it is usually a sign that they didn't drink enough. Unless you are pushing way too big of a gear and tearing up your leg muscles, if you fuel and hydrate properly you should feel just as good at the end of the ride as at the beginning.
The difference between "just riding" and actually training with a purpose is that when you train you must recognize that every workout has a purpose. This is easy for us to forget in the fall and winter months when many of us are coming off of less structured periods of training and beginning base training composed primarily of endurance rides. Yet many of us look forward to this time of the year as a time when we can enjoy the longer, lower intensity, more social rides without the stress of a lot of intensity training, racing and traveling. Don't be misled though; there is much more to an endurance ride than "just riding". Like any other workout, an endurance ride serves a specific purpose and if done incorrectly can at best be of little training value and at worst lead to over-reaching (and ultimately over-training), injury and burnout.
Purpose of endurance rides:
- Mechanical efficiency. Though one-legged drills, fast cadence drills, riding a fixed gear bike and rollers can all help make your pedal stroke more efficient, the simple act of pedaling thousands or even millions of pedal strokes may do the most to make your pedaling as smooth and even as possible. All of this repetition should also help you to identify any bike fit or body misalignment issues (i.e. if you need to see a doctor or a chiropractor)
- Metabolic efficiency. Lower intensity rides (zones 1-3) will help teach the body to burn fat as a primary energy source. When we do Lactate Threshold tests in our lab, we can always tell when people need to spend more time developing their aerobic base because they accumulate lactic acid even at relatively low intensities (zone 1-2). Since lactic acid is a bi product of anaerobic energy production, premature lactate accumulation is a sure sign that these riders need to develop the ability to efficiently metabolize fat for energy. Burning muscle glycogen (which is in limited supply) for energy rather than fat (which there is a large supply of even in the leanest athletes) means that you will not be able to make the key high intensity efforts when it really counts.
- Improve the body's ability to transport blood and oxygen. When we talk about "aerobic fitness" this is primarily what we are talking about. High intensity exercise can also accomplish this, but these levels cannot be sustained as long and repeated bouts of high intensity exercise every day can lead to overreaching, illness and injury. Development of aerobic fitness will mean that the body will respond better to the intensity workouts that come later on.
- Muscular strength. Though muscle mass will be generated more effectively in the gym, on the bike strength training is what will make this muscle mass more functional on the bike. In order to keep heart rate and power in zone 2 uphill, it is often necessary to pedal at very low rpms. If you are able to stay seated with good form this can be an opportunity not only to keep your heart rate and power down, but also to work on cycling-specific muscular strength.
- Fat Loss. Though you will more fat in a 1 hour ride at LT than you will on a 1 hour endurance ride, you won't be able to do 1 hour LT rides every day, whereas most experienced riders are capable of completing 4, 5, and even 6 hour endurance rides on a regular basis. A typical cyclist will burn 350-800 kCal.hour on the bike, so if you need to shed some extra pounds before spring there is no better way to do it than to add endurance volume while monitoring your Caloric intake. You will still have to consume more Calories when you increase your training volume though. Cut out desserts, junk food and alcohol and cut portion size at dinner, especially on your light days or off days. Don't starve yourself on the bike. The more you eat on your rides, the more Calories you will burn and the better you will feel. If you are losing more than 1 pound per week (a caloric deficit of 500 kCal), you are losing weight too fast and should increase energy consumption and/or reduce training volume.
So how do we accomplish all of these goals most appropriately? When I examine power files from an athlete's endurance ride, this is what I look for:
- No more than 5% of the time above zone 2 heart rate. There will be times where it is difficult if not impossible to keep your heart rate down in zone 2. A little time in zone 3 is OK, but try to avoid extended periods above the upper limit of zone 2 HR.
Two graphs of heart rate distribution by zone. The first shows 11% in zone 1 and 89% in zone 2. The second shows 25% of the time above zone 2.
- Average power in zone 2. For most riders, average power for an endurance ride will fall in the low end of zone 2. Many riders go way too hard uphill and then coast or soft-pedal downhill on their endurance rides, which is more like hill sprints than endurance. Most will see power numbers at the high end of zone 3 while riding uphill and at the low end of zone 2 while riding downhill.
- Normalized power in zone 2. Normalized power better quantifies the difficulty of a ride with non-steady state efforts. I look for normalized power to be a bit higher than average power, but still in zone 2. A good endurance ride should be a relatively steady state power output, which means that the normalized power should not be dramatically higher than average power. We often describe this as "using your power meter to flatten the ride".
- Average cadence over 85. Though there will be periods of low cadence (uphill) and periods where cadence is zero (coasting), if you are pedaling, your cadence should be be 90-100 rpm unless otherwise prescribed by your coach. Factoring in uphills and coasting should produce an overall average cadence of 85 rpm or higher.
- No more than 10% coasting. Any ride will include periods of coasting such as approaching lights and stop signs and riding down steep and windy descents and this is fine. However, it is important to try to keep pedaling whenever possible. Time spent coasting is essentially time wasted. Practice shifting regularly so that you can keep your power where it needs to be on any grade. If your significant other ever gives you grief about riding your bike too much, just think of they would say when you tell them that you spent 20% of that time coasting!
- Normalized power in zone 2. Normalized power better quantifies the difficulty of a ride with non-steady state efforts. I look for normalized power to be a bit higher than average power, but still in zone 2. A good endurance ride should be a relatively steady state power output, which means that the normalized power should not be dramatically higher than average power. We often describe this as "using your power meter to flatten the ride".
- Average cadence over 85. Though there will be periods of low cadence (uphill) and periods where cadence is zero (coasting), if you are pedaling, your cadence should be be 90-100 rpm unless otherwise prescribed by your coach. Factoring in uphills and coasting should produce an overall average cadence of 85 rpm or higher.
- No more than 10% coasting. Any ride will include periods of coasting such as approaching lights and stop signs and riding down steep and windy descents and this is fine. However, it is important to try to keep pedaling whenever possible. Time spent coasting is essentially time wasted. Practice shifting regularly so that you can keep your power where it needs to be on any grade. If your significant other ever gives you grief about riding your bike too much, just think of they would say when you tell them that you spent 20% of that time coasting!
A graph of cadence distribution during one group ride shows 19% of the time coasting (0 rpm)
- Steady power output and heart rate throughout the ride without a significant fade. If a rider's power drops dramatically towards the end of the ride, it is probably a sign that they didn't eat enough. If their heart rate rises dramatically, it is usually a sign that they didn't drink enough. Unless you are pushing way too big of a gear and tearing up your leg muscles, if you fuel and hydrate properly you should feel just as good at the end of the ride as at the beginning.
A smoothed power curve from a 3.5 hour ride shows a definite drop in power. This rider did not eat enough and his power dropped 38% in the last hour of the ride.
One of the big questions riders ask about endurance-base rides is "Can I do group rides?". Group rides can often be "hammer-fests" with periods of very high intensity (usually up hills and in sprints) even if advertised as "easy winter endurance riding". For most riders, keeping heart rate and power in zone 2 and coasting time limited is difficult if not impossible. These rides may serve a purpose, but let me be clear here, they are not endurance rides. If you want to ride with a group and still accomplish the goals of the endurance ride, my advice would be to find the rides that the local pros and elite racers do. These guys may be able to race fast, but they also know how to ride slow (and do their endurance rides the right way). If you compete 9 months of the year, you look forward to the 3 months of the year when you can ride easy. Riding with experienced athletes can also be a great opportunity to pick their brains and get valuable insight into training and racing.
On the other side of the coin, if you happen to be of the stronger riders yourself, you may find that the group rides available are simply too easy. This is where riding a fixed gear bike can be extremely valuable. The uphills will help you work on cycling specific muscular strength, the downhills will help you develop leg speed and overall the fixed gear acts as a "handicap", allowing you to get a bit more out of the ride while still being able to enjoy the social aspects. If you are riding a fixed gear when other riders are on road bikes, make sure use fairly light gearing (e.g. 39x16 or 42x17), install at least one brake, and make sure to stay out of the way of the other riders on the downhills, as you will not be able to go as fast as you would on a bike that can freewheel. If you are not confident in your handling ability on the fixed gear bike, you should probably ride towards the back of the group.
As your aerobic base starts to develop, I recommend increasing the length of your longest rides to just over the duration of your longest races or events, so if your longest race will be 4 hours, your longest rides should be 4 hours. Rides much longer that this will be of limited benefit to you unless you need to lose a great deal of weight. In the later stages of base training, start to incorporate in more hills into your rides. While you should still try to stay seated and keep your heart rate in zone 2, try to carry your momentum over the small climbs better even if it leads to a short spike in power.
On the other side of the coin, if you happen to be of the stronger riders yourself, you may find that the group rides available are simply too easy. This is where riding a fixed gear bike can be extremely valuable. The uphills will help you work on cycling specific muscular strength, the downhills will help you develop leg speed and overall the fixed gear acts as a "handicap", allowing you to get a bit more out of the ride while still being able to enjoy the social aspects. If you are riding a fixed gear when other riders are on road bikes, make sure use fairly light gearing (e.g. 39x16 or 42x17), install at least one brake, and make sure to stay out of the way of the other riders on the downhills, as you will not be able to go as fast as you would on a bike that can freewheel. If you are not confident in your handling ability on the fixed gear bike, you should probably ride towards the back of the group.
As your aerobic base starts to develop, I recommend increasing the length of your longest rides to just over the duration of your longest races or events, so if your longest race will be 4 hours, your longest rides should be 4 hours. Rides much longer that this will be of limited benefit to you unless you need to lose a great deal of weight. In the later stages of base training, start to incorporate in more hills into your rides. While you should still try to stay seated and keep your heart rate in zone 2, try to carry your momentum over the small climbs better even if it leads to a short spike in power.
A good aerobic base will help prepare you for higher intensity training and racing to come. It will allow you to respond to theses stresses better and recover faster. Many may view endurance rides as "just riding", but paying attention to the details of these rides, being disciplined and patient will lead to results. Riding how you feel and ignoring the details will lead to fitness built on a shaky foundation and it will ultimately fall over like a house of cards.
Sunday, December 16, 2007
Cadence Bike Fit and Dartfish Video Analysis
Minus a pair of Zipp 999’s one of the easiest ways to increase cycling performance can be acquired in as little as two hours. A proper bike fit is the most overlooked factor in cycling performance and one of the easiest ways to increase speed. In the wrong position, an increase in fitness will not always transfer to increased speed. Correct positioning is the result of cycling experience, previous injuries, body size, flexibility, and technique.
Cycling experience is important factor because it is important to know how long an athlete has been riding in a certain position. Due to our adaptable nature it is possible to ride a saddle two inches below optimal but you will not activate the hamstring and gluteal muscles correctly, and for sure this will limit the amount of power generated.
Previous injuries can have a huge impact on your cycling position. A broken ankle from 15 years ago can change riding symmetry and result in imbalances. Many imbalances can be corrected or reduced by shimming, tiling, offsetting, etc. An experienced fit specialist will be able to explain which option is ideal for a given circumstance.
Correct cycling position is a question of arranging three contact points between the rider and bike: 1.Where the feet clip into the pedals, 2.Where the sit bones contact the saddle, 3.Where the hands/elbows hold the handlebars. The cleats are the only contact point locked into position and changes here can influence the action of the entire leg. Seat height and fore/aft position influence the transfer of power between the legs and the pedals. Aerobar height determines comfort and aerodynamics but be careful, bars that are too low relative to seat height can decrease power production. For triathletes, these factors are especially important because they must be maintained while trying to get the athlete as low and aerodynamic as possible.
A comprehensive bike fit that includes a dynamic assessment, using tools like Dartfish video analysis software, can determine if cycling posture and pedaling mechanics need improvement. This software can reveal problems with joint motions and display pre and post positions simultaneously using an overlay function that can fade in and out between the two. This software can also determine if changes made to the bike affect technique or dynamic fit, i.e. how an increase in seat height can increase ankle plantar flexion. These changes to form are not always readily apparent visually, but by using slow motion video playback or zooming in on a joint angle it can be very discernible.
The figure above displays some of the analysis tools of Dartfish. This software can accurately determine joint angles and provides instant feedback to dial in the perfect position. This rider is too compact and low on the bike in the pre position, picture on the left. By increasing seat height, moving the saddle forward, and changing the bar position the hip and knee angles increase at the top of the pedal stroke. This change increases the mechanical advantage and the power he can generate in an aerodynamic position. These changes also brought the arm angle in tighter decreasing the tension and stress on his upper body musculature.
This video analysis tool also allows us to see changes post fit otherwise not obvious with the naked eye. An increase in seat height may cause excessive planter flexion of the foot or reaching of the toes at bottom dead center of the pedal stroke. Trying to see this with the naked eye can be difficult but slowing down captured video or viewing an overlay of pre and post positions can make this very detectable. Too much planter flexion is a sign the seat has moved to high, too soon.
With all of the time and money we invest in the sport why limit your performance with a poor cycling position. A professional fit is one of the easiest ways to maximize your abilities and conserve as much energy as possible to make your overall triathlon event as successful as possible.
Cycling experience is important factor because it is important to know how long an athlete has been riding in a certain position. Due to our adaptable nature it is possible to ride a saddle two inches below optimal but you will not activate the hamstring and gluteal muscles correctly, and for sure this will limit the amount of power generated.
Previous injuries can have a huge impact on your cycling position. A broken ankle from 15 years ago can change riding symmetry and result in imbalances. Many imbalances can be corrected or reduced by shimming, tiling, offsetting, etc. An experienced fit specialist will be able to explain which option is ideal for a given circumstance.
Correct cycling position is a question of arranging three contact points between the rider and bike: 1.Where the feet clip into the pedals, 2.Where the sit bones contact the saddle, 3.Where the hands/elbows hold the handlebars. The cleats are the only contact point locked into position and changes here can influence the action of the entire leg. Seat height and fore/aft position influence the transfer of power between the legs and the pedals. Aerobar height determines comfort and aerodynamics but be careful, bars that are too low relative to seat height can decrease power production. For triathletes, these factors are especially important because they must be maintained while trying to get the athlete as low and aerodynamic as possible.
A comprehensive bike fit that includes a dynamic assessment, using tools like Dartfish video analysis software, can determine if cycling posture and pedaling mechanics need improvement. This software can reveal problems with joint motions and display pre and post positions simultaneously using an overlay function that can fade in and out between the two. This software can also determine if changes made to the bike affect technique or dynamic fit, i.e. how an increase in seat height can increase ankle plantar flexion. These changes to form are not always readily apparent visually, but by using slow motion video playback or zooming in on a joint angle it can be very discernible.
The figure above displays some of the analysis tools of Dartfish. This software can accurately determine joint angles and provides instant feedback to dial in the perfect position. This rider is too compact and low on the bike in the pre position, picture on the left. By increasing seat height, moving the saddle forward, and changing the bar position the hip and knee angles increase at the top of the pedal stroke. This change increases the mechanical advantage and the power he can generate in an aerodynamic position. These changes also brought the arm angle in tighter decreasing the tension and stress on his upper body musculature.
This video analysis tool also allows us to see changes post fit otherwise not obvious with the naked eye. An increase in seat height may cause excessive planter flexion of the foot or reaching of the toes at bottom dead center of the pedal stroke. Trying to see this with the naked eye can be difficult but slowing down captured video or viewing an overlay of pre and post positions can make this very detectable. Too much planter flexion is a sign the seat has moved to high, too soon.
With all of the time and money we invest in the sport why limit your performance with a poor cycling position. A professional fit is one of the easiest ways to maximize your abilities and conserve as much energy as possible to make your overall triathlon event as successful as possible.
Thursday, December 13, 2007
How do I know if I need a bike fit?
Here at Cadence, we never cease to be amazed at how many people out there are not fit well on their bikes. I am not just talking about small issues; I'm talking about seats 3 inches too low, stems 4 cm too long and bikes 3 sized too small. The truth is, our bodies are capable of adapting to a lot. Many people do not know they have a bad fit because they don't know what it feels like to be comfortable. Maybe they just assume that riding a bike is a painful experience because that is the way it has always been for them. So I am here to tell you that it doesn't have to be that way! A good bike fit can make you more comfortable, more powerful, more efficient and more aerodynamic as well as making the bike handle better and be safer to ride.
Friday, December 7, 2007
Power Demands of Cyclocross Racing: Part 3
The cyclocross season is now over for many of us. For those going to Nationals in Kansas City there is one more week before the cross bikes get hung up on the hooks for the winter (that is, unless you are planning on going to World's). Coach Mike Kuhn and I had a great time going to cross races this season in the PA Series, the MAC series and the two USGPs in Trenton. With the help of Cycle-Ops, we were able to provide 10 trainers for riders to warm up on under the shelter of our tents. We were also able to get some racers to demo some sweet PowerTap 2.4 wireless wheels in their races. We were pleased to see that the wheels look good as new even after some serious abuse and riding in extreme conditions. These riders also provided us with some valuable data about the demands of cross racing.
In the first part of this series, I listed the summary data for a number of riders riding in the same race (Spring Mountain Cross). The power files we collected showed how cyclocross is extremely non-steady state, meaning that there are huge spikes in power followed by periods of zero power (while the rider is coasting, braking or running) and low power (while the rider is soft pedaling through technical sections). I theorized that the more technically proficient riders were able to spend more time pedaling, less time coasting and braking and they applied less braking force. This meant that they did not slow down as much and in turn did not have to make as much of an effort to re-accelerate. As evidence of this, the riders that performed better typically spent less time at sub-maximal power levels (defined as power outputs greater than 5.5 watts/kg) and had more "in the tank" at the end of the race to make an attack, follow an attack or close the gap on the rider in front.
Don't make the mistake that cyclocross, or any type of bike racing for that matter, is simply a matter of numbers. Certainly, riders that are more technically proficient are able conserve better and use their power when they need it most. This hardly means that the race is a lock though. The great thing about bike racing is that given the right circumstances, any rider may have the opportunity to win. The key for each rider is to design their training and race tactics well in order to have the greatest odds of success. In doing this, the power meter can be a very useful tool.
Let me give a few case studies of riders from different backgrounds, strengths and weaknesses to illustrate how we might put together a training plan and a race strategy tailored to each individual:
Dave will clearly have difficulty making the hard accelerations that occur many times in cross races. In terms of race strategy, Dave will fair much better if he can ride in the front of a group. This will allow him to choose better lines and take the technical sections at speed instead riding behind less technically proficient riders and having to slow down and then sprint out of every turn. Riders behind him will not be able to take these sections as fast and will still have to make those jumps, which will wear them down. That said, Dave needs to get in front to begin with, to do that he needs to improve his sprint. It would benefit Dave to practice some cyclocross starts. To do these, you start with one foot down and then clip in as quickly as possible, go all out for 2 minutes and then settle into a pace that is just above functional threshold power for an additional 3 minutes. Although no cross race will have 5 minute periods of sustained power, this will help Dave practice the start of the race as well as improve his upper-end aerobic capacity. With practice, he should start to see the his power for the initial 2 minutes rise considerably.
Kurt is a very different case. His numbers indicate that he should be able to start well and get up to the front of the pack quickly. However, his lack of technical skills will make it more difficult on him than many other riders and he will get worn down throughout the race because he will decellerate more, and thereby have to accelerate much harder. The most important thing for Kurt is to get used to riding off road. Buying or borrowing a mountain bike and riding the trails once or twice a week could be of great benefit to him, and it could also be a fun way to maintain his endurance. If he is unable to get a mountain bike, riding his cross bike on some mountain bike trails can be equally and often even more beneficial. Because a cross bike has no suspension, you have to pick your lines very carefully. In sections that are too technical to ride, pick up the bike and run it. If you have a choice of trails, try to find terrain with a lot of twists and turns and avoid overly rocky sections, as they are unlike anything you would encounter in a cross race. Of course, use caution when doing these rides because there is little room for error when you are riding with no suspension. For more cross specific work, Kurt should also look for a weekly group cross workout. He should spend extra time working on skills such as dismounts and remounts, off-camber cornering and riding over loose surfaces. When riding off-road, look for low power averages and non-steady state power output. As you get more comfortable, try to spend more time pedaling and less time coasting or braking, which will result in higher power averages for the same relative level of exertion.
Like Dave, Kurt will want to ride in the front of his group if possible. Since he can accelerate faster than most others, he can use this to his advantage if he is in front because everyone behind him will also have to slow down more and re-accelerate harder. Riding like this could be a death sentence to a rider like Kurt. If you are worried that this type of riding will break the rules of cycling etiquette, don't be. Remember, it's a race!
Since Bob is not an experienced racer, he will have to build more general fitness than either Dave or Kurt. Although his races will last only 30-40 minutes, it is still important for him to develop his endurance by completing at least 1 longer endurance ride (2+ hours) every week. In cross season, this is best done on a cross bike because it will help you get more comfortable on the bike. If you have access to fire roads or dirt roads, riding on this kind of terrain can be ideal. As far as cross specific fitness goes, it is very likely that Bob needs to improve his ability to make repeated sprints. An excellent workout for this is a cross version of suicide drills. Anyone who has played basketball knows what I am talking about here, but for those that weren't subjected to that torture in 5th grade gym class, suicide drills are where you run as fast as you can to the foul line, turn around, run back, then sprint to the half court line, then back, then to the far foul line then back, etc... For cross, you can do these on a soccer or football field at 30, 50, 70 and 100 yards. Sprint as hard as you can off the line and make a quick 180 at the line, trying to turn in as small of a radius as possible. Make sure that you don't get bogged down in you gear and you are sprinting all out after each line. Complete 4-8 sets of these with 5 minutes recovery in between sets. Like the basketball version, it is not unusual to feel a bit nauseous. Look at your power files afterwards to see your max and 5 second power for the sprints as well as how well you are able to maintain that power as you fatigue.
Finally, like Dave and Kurt, Bob should also try to do a weekly group cross workout to prepare for the specific demands of cross racing. The one thing that Bob needs to be a bit more careful about, however, is not overdoing it. As an older rider it will take him longer to recover from his workouts than Dave or Kurt, and I would bet that if he did a group cross workout Tuesday, endurance ride on Wednesday and cross suicide drills on Thursday, he would still be tired on Saturday when the race rolls around, meaning that he would not be performing at 100%. Remember that training is a balance of stress and recovery. Doing more training than you can recover from will only lead to fatigue, illness, injury and burnout. It can be useful to examine your Training Stress Balance, or TSB (for definition, see my blog posted on 11/2). If the race is a A or B priority, the TSB should be positive going into the weekend.
For race strategy, the most important thing for Bob is to be realistic. He should look at the riders that are placing just in front of him in early season races and try to stay with them. If Bob has no realistic chance of placing in the top 10, it won't help him to kill himself to try to get to the front of the pack at the start. His best bet is to find riders that are just a little bit better than he is, try to stay with them and hopefully beat them. As he starts to do this, his goals may become more ambitious and when he starts to consistently finish in the top 5 it is probably time to upgrade.
Good luck to all those racing at National Championships this weekend and a happy winter to everyone else! I hope you have enjoyed this series of articles and I encourage you to send me any comments or questions that you may have. Thanks for reading!
In the first part of this series, I listed the summary data for a number of riders riding in the same race (Spring Mountain Cross). The power files we collected showed how cyclocross is extremely non-steady state, meaning that there are huge spikes in power followed by periods of zero power (while the rider is coasting, braking or running) and low power (while the rider is soft pedaling through technical sections). I theorized that the more technically proficient riders were able to spend more time pedaling, less time coasting and braking and they applied less braking force. This meant that they did not slow down as much and in turn did not have to make as much of an effort to re-accelerate. As evidence of this, the riders that performed better typically spent less time at sub-maximal power levels (defined as power outputs greater than 5.5 watts/kg) and had more "in the tank" at the end of the race to make an attack, follow an attack or close the gap on the rider in front.
Don't make the mistake that cyclocross, or any type of bike racing for that matter, is simply a matter of numbers. Certainly, riders that are more technically proficient are able conserve better and use their power when they need it most. This hardly means that the race is a lock though. The great thing about bike racing is that given the right circumstances, any rider may have the opportunity to win. The key for each rider is to design their training and race tactics well in order to have the greatest odds of success. In doing this, the power meter can be a very useful tool.
Let me give a few case studies of riders from different backgrounds, strengths and weaknesses to illustrate how we might put together a training plan and a race strategy tailored to each individual:
Bob: 40 year old recreational rider/Cat. 5 road racer. He did a few road races last year but decided to give cross a try because he likes the laid back atmosphere. Although he loves to do group rides on weekends, he feels a bit intimidated by the pack aspect of road races. Bob owns a mountain bike and rides it occasionally but has never raced it. Bob is 5'10" and 180 lbs. His Functional Threshold Power is 275, his 5 sec. MMP is 1000 watts, his 1 minute MMP is 500 watts and his 5 minute MMP is 330 watts.
Dave will clearly have difficulty making the hard accelerations that occur many times in cross races. In terms of race strategy, Dave will fair much better if he can ride in the front of a group. This will allow him to choose better lines and take the technical sections at speed instead riding behind less technically proficient riders and having to slow down and then sprint out of every turn. Riders behind him will not be able to take these sections as fast and will still have to make those jumps, which will wear them down. That said, Dave needs to get in front to begin with, to do that he needs to improve his sprint. It would benefit Dave to practice some cyclocross starts. To do these, you start with one foot down and then clip in as quickly as possible, go all out for 2 minutes and then settle into a pace that is just above functional threshold power for an additional 3 minutes. Although no cross race will have 5 minute periods of sustained power, this will help Dave practice the start of the race as well as improve his upper-end aerobic capacity. With practice, he should start to see the his power for the initial 2 minutes rise considerably.
Kurt is a very different case. His numbers indicate that he should be able to start well and get up to the front of the pack quickly. However, his lack of technical skills will make it more difficult on him than many other riders and he will get worn down throughout the race because he will decellerate more, and thereby have to accelerate much harder. The most important thing for Kurt is to get used to riding off road. Buying or borrowing a mountain bike and riding the trails once or twice a week could be of great benefit to him, and it could also be a fun way to maintain his endurance. If he is unable to get a mountain bike, riding his cross bike on some mountain bike trails can be equally and often even more beneficial. Because a cross bike has no suspension, you have to pick your lines very carefully. In sections that are too technical to ride, pick up the bike and run it. If you have a choice of trails, try to find terrain with a lot of twists and turns and avoid overly rocky sections, as they are unlike anything you would encounter in a cross race. Of course, use caution when doing these rides because there is little room for error when you are riding with no suspension. For more cross specific work, Kurt should also look for a weekly group cross workout. He should spend extra time working on skills such as dismounts and remounts, off-camber cornering and riding over loose surfaces. When riding off-road, look for low power averages and non-steady state power output. As you get more comfortable, try to spend more time pedaling and less time coasting or braking, which will result in higher power averages for the same relative level of exertion.
Like Dave, Kurt will want to ride in the front of his group if possible. Since he can accelerate faster than most others, he can use this to his advantage if he is in front because everyone behind him will also have to slow down more and re-accelerate harder. Riding like this could be a death sentence to a rider like Kurt. If you are worried that this type of riding will break the rules of cycling etiquette, don't be. Remember, it's a race!
Since Bob is not an experienced racer, he will have to build more general fitness than either Dave or Kurt. Although his races will last only 30-40 minutes, it is still important for him to develop his endurance by completing at least 1 longer endurance ride (2+ hours) every week. In cross season, this is best done on a cross bike because it will help you get more comfortable on the bike. If you have access to fire roads or dirt roads, riding on this kind of terrain can be ideal. As far as cross specific fitness goes, it is very likely that Bob needs to improve his ability to make repeated sprints. An excellent workout for this is a cross version of suicide drills. Anyone who has played basketball knows what I am talking about here, but for those that weren't subjected to that torture in 5th grade gym class, suicide drills are where you run as fast as you can to the foul line, turn around, run back, then sprint to the half court line, then back, then to the far foul line then back, etc... For cross, you can do these on a soccer or football field at 30, 50, 70 and 100 yards. Sprint as hard as you can off the line and make a quick 180 at the line, trying to turn in as small of a radius as possible. Make sure that you don't get bogged down in you gear and you are sprinting all out after each line. Complete 4-8 sets of these with 5 minutes recovery in between sets. Like the basketball version, it is not unusual to feel a bit nauseous. Look at your power files afterwards to see your max and 5 second power for the sprints as well as how well you are able to maintain that power as you fatigue.
Finally, like Dave and Kurt, Bob should also try to do a weekly group cross workout to prepare for the specific demands of cross racing. The one thing that Bob needs to be a bit more careful about, however, is not overdoing it. As an older rider it will take him longer to recover from his workouts than Dave or Kurt, and I would bet that if he did a group cross workout Tuesday, endurance ride on Wednesday and cross suicide drills on Thursday, he would still be tired on Saturday when the race rolls around, meaning that he would not be performing at 100%. Remember that training is a balance of stress and recovery. Doing more training than you can recover from will only lead to fatigue, illness, injury and burnout. It can be useful to examine your Training Stress Balance, or TSB (for definition, see my blog posted on 11/2). If the race is a A or B priority, the TSB should be positive going into the weekend.
For race strategy, the most important thing for Bob is to be realistic. He should look at the riders that are placing just in front of him in early season races and try to stay with them. If Bob has no realistic chance of placing in the top 10, it won't help him to kill himself to try to get to the front of the pack at the start. His best bet is to find riders that are just a little bit better than he is, try to stay with them and hopefully beat them. As he starts to do this, his goals may become more ambitious and when he starts to consistently finish in the top 5 it is probably time to upgrade.
Good luck to all those racing at National Championships this weekend and a happy winter to everyone else! I hope you have enjoyed this series of articles and I encourage you to send me any comments or questions that you may have. Thanks for reading!
Monday, November 12, 2007
Power Demands of Cyclocross Racing: Part 2
It was another exciting round of cyclocross racing in New Jersey at Beacon and Highland Park this past weekend; both were UCI races and part of the Mid-Atlantic Cross Series. Davide Frattini and Georgia Gould won both days with the right combination of form and fitness. Georgia impressed us all by winning the Men's B race on Saturday and placing well again on Sunday (starting at the back of the field both days) before riding away from all her competitors in the women's races both days.
Last week I posted power numbers for some of the riders that rode with PowerTap wheels in the Spring Mountain race. Just to refresh, a few things immediately stand out about these files:
1. Very non steady-state efforts
2. Relatively low power; far less than what the riders would be capable of producing for a steady-state effort of the same duration.
3. Low cadence. Average cadences were 67-80 rpm.
So what makes cyclocross so hard? It certainly isn't the high average power, or even normalized power. Is it the low cadence? Is it the running? How important is technical ability? Does better technique mean that a rider will not have to put out as much power to go the same speed? And finally, what qualities make a good cross racer?
When you look at power files from any cyclocross race, there are 3 "modes" that a racer will be in almost all the time:
1. Sub-Maximal. This is the point that is just short of a sprint, about a 9.5 out of 10 on the intensity scale. In non-technical sections with good traction and no obstacles, riders can really lay down the power. These efforts can range anywhere from 2-3 seconds up to about 30 seconds on courses with long open sections. In the course of a 60 minute race a rider may have to make up to 200 of these efforts. Though the length of the efforts is highly course dependant, they are rarely over 30 seconds. Since Normalized Power is calculated using a 30 second rolling average, that number will not truly reflect the difficulty of the race like it will in criteriums and road races that include regular 30 second+ hard efforts.
Last week I posted power numbers for some of the riders that rode with PowerTap wheels in the Spring Mountain race. Just to refresh, a few things immediately stand out about these files:
1. Very non steady-state efforts
2. Relatively low power; far less than what the riders would be capable of producing for a steady-state effort of the same duration.
3. Low cadence. Average cadences were 67-80 rpm.
So what makes cyclocross so hard? It certainly isn't the high average power, or even normalized power. Is it the low cadence? Is it the running? How important is technical ability? Does better technique mean that a rider will not have to put out as much power to go the same speed? And finally, what qualities make a good cross racer?
When you look at power files from any cyclocross race, there are 3 "modes" that a racer will be in almost all the time:
1. Sub-Maximal. This is the point that is just short of a sprint, about a 9.5 out of 10 on the intensity scale. In non-technical sections with good traction and no obstacles, riders can really lay down the power. These efforts can range anywhere from 2-3 seconds up to about 30 seconds on courses with long open sections. In the course of a 60 minute race a rider may have to make up to 200 of these efforts. Though the length of the efforts is highly course dependant, they are rarely over 30 seconds. Since Normalized Power is calculated using a 30 second rolling average, that number will not truly reflect the difficulty of the race like it will in criteriums and road races that include regular 30 second+ hard efforts.
2. Coasting. No power is applied to the pedals. This could occur going down a hill, into a turn or into the barriers. These efforts typically range from 1-5 seconds.
3. Braking. Although braking and coasting will both register as zero power, I will make the distinction here because braking is actually the application of additional opposing force. Remember my definition of Speed = [Power - opposing force]. On a flat road, about 85% of the opposing force is from aerodynamic drag with the other 15% from gravity, rolling resistance and drivetrain resistance. When a rider goes uphill, more of the resistance is from gravity and as they slow down the amount of aerodyamic drag increases. Off road, aerodynamic resistance is minimal because of the slower speeds, but rolling resistance is much more significant. Braking force is rarely considered in road racing because the brakes are used so infrequently, but it is highly significant off road. So maybe before you go on that crash diet and try to lose 10 lbs, you should ask yourself if you could brake a little less, or perhaps not quite as hard.
4. Soft Pedaling. These are the sections that are too technical for a rider to go full throttle, but they can still pedal through. These usually occur around tight turns or off-camber sections of the course. These efforts are usually 3-10 seconds in duration. Power output is typically in the recovery or endurance zones.
What is conspicuously missing here are the long steady state efforts that would occur often in road racing and even in mountain biking.
If we examine in detail the file of a technically proficient rider, you will see that they spend less time coasting and more time pedaling. A good technical rider is still soft-pedaling when others are coasting. This means that they will come much closer to actually producing the power they are capable of (as we saw with Kyle last week).
The other factor is that the better technical rider makes less severe decellerations. Less severe decelleration means that the reacceleration is also less severe. Think of it this way: every time you lose speed through an obstacle you have to get back up to speed after you clear the obstacle. If you don't lose as much speed, you don't have to apply as much power or apply power for as long to get back up to speed. This energy savings adds up. Though some of us have more matches to burn than others, no one has an unlimited number of matches. Every re-acceleration takes energy and causes muscular fatigue, so a rider that is constantly slamming on his brakes and then sprinting back up to speed is at a distinct disadvantage and most likely won't have much left at the end of the race to sprint, attack or chase.
As evidence of this, we can examine a couple close races at Spring Mountain. In the B race, Woody and Johann were 2nd and 3rd, respectively, and finished only 5 seconds apart. Woody, as the better technical rider, spent 8 minutes and 27 seconds (~19%) at sub-maximal power levels (>5.5 watts/kg) whereas Johann spent 9 minutes and 11 seconds (~20%) in that zone. In the elite race, we can examine John (4th place) and Colin (5th place) who finished 1 minute apart. John spent 13 minutes and 10 seconds (21%) at sub-maximal power levels compared to Colin's 15 minutes and 24 seconds (25%).
So, what does it take to be a good cross racer?
1. The ability to make repeated sub-maximal efforts with little recovery.2. Good technical skills: more time pedaling, less time coasting, less time braking and less severe braking. This of course, should all be done while keeping it upright :)3. Good muscular strength. This is necessary because of the low cadence/high torque nature of the sport. Of course, there are other factors as well, such as being able to start a race with a 15-30 second all out sprint, transitioning on and off the bike well, being able to run with the bike, and of course, a lot of mental toughness. Next week I will talk about how we can create workouts and race strategies that will best capture the unique demands of cross racing and help racers minimize their weaknesses and maximize their strengths.This weekend Trenton will host the biggest weekend of cross racing on the East Coast, so I hope to see you all out there with your cowbells!
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